In batteries using air cathodes and consumable metal anodes, there have been proposed forms into which electrodes can be secured. In U.S. Pat. No. 4,246,324, box-like forms have been used with electrodes that are positioned on opposing faces of the form. Electrolyte is maintained between the facing electrodes and the consumable anode can be of plate shape, secured in the box-like form by spring clips.
In the U.S. Pat. 4,091,174 there have been shown rod-shaped consumable electrodes. These can be secured in apertures of similar concentric shape and springs may be useful for maintaining this particularly shaped consumable electrode closely adjacent an air electrode. As shown in the U.K. Patent No. 1,223,127 the air electrode may be separated from the consumable electrode by strips across the face of a plate-like air electrode. Furthermore, these strips may have projections, like tiny nubs, that maintain a spacing between a consumable electrode, which can be in plate-like form and the air electrode. A sequence of these members are taught to be capable of being bound together and then external spring can be wrapped around such bound grouping for maintaining pressure between the internal battery members.
It has been more recently taught in the U.S. Pat. No. 4,693,946, that the air cathode can be provided as a module. The module can have a screen surface reinforcement on the cathode face and such elements are firmly crimped and sealed into a metal frame, thereby providing a module. The cathode can be spaced apart from the consumable anode by a cage which serves as an anode holder. The cage may be V-shaped, whereby useful anodes are wedge-shaped.
It has also recently been shown in U.S. Pat. No. 4,551,399 that the cathode can be mounted on arms, and the arms wired. The arms can then penetrate through a separator wall and thereby be in contact with an anode on the far side of the wall. The anode may be wedge shaped with the backside conforming with the straight separator wall and the angled side being in a plane parallel to the plane of the cathode.
Ribs running across the face of a cathode, maintaining anode/cathode separation, have also been shown to be useful in the U.S. Pat. No. 4,389,466. On the cathode backside, a porous, rigid support may be used. The porositY of the support permits air to flow through the support element and yet be in contact with the cathode. On the anode side, an expandable bladder is used to maintain pressure on the anode and force it against the ribs to make good electrical contact between ribs and anode. Alternatively, as shown in the more recent U.S. Pat. No. 4,560,626, the bladder can be used in conjunction with coiled springs maintained at the same part of the battery as the bladder. The bladder is again useful for maintaining internal pressure. However, during anode replacement, the internal springs can be useful, against the pressure of the bladder, for retracting the cathode away from the anode so that the anode can be easily replaced.
Most recently in U.S. patent application Ser. No. 056,567 it has been taught to provide a current collector member within a cell, with such member having compressible elements that at least assist in the force holding internal cell parts together. These compressible elements can extend across a cell air space and be in contact with an electrically conductive, foraminous metal member. By such means it has been possible to produce a bipolar battery of excellent energy efficiency.
It is apparent that many desirable features have therefore been investigated in many aspects of providing a more long life operation to batteries employing consumable electrodes. However, certain combinations of features, packaged in efficient manner, and including a bipolar battery package of a lighter weight and compactness would still be highly desirable. Maintenance of a sealed cell to prevent electrolyte loss and allow pressure operation would be advantageous.